Air Insulated Switchgear - Air insulated systems remain cost-effective and reliable for outdoor installations with simple maintenance requirements.
Air Insulated Switchgear (AIS) is the conventional and most foundational technology for high-voltage power switching and protection. In an AIS substation, live components are mounted on insulators and separated by the insulating medium of ambient air at normal atmospheric pressure. The simplicity of its design allows for a lower initial investment and makes maintenance procedures relatively straightforward, as all components are readily accessible for visual inspection and repair.
However, the requirement for air as the primary insulator necessitates large electrical clearance distances to prevent flashovers, resulting in a very large physical footprint. This reliance on open air also makes the equipment susceptible to environmental factors, including high altitude (which reduces air's dielectric strength), pollution, dust, and inclement weather, all of which can compromise performance and necessitate regular, often intensive, cleaning and maintenance cycles to maintain reliability. AIS remains the default choice in rural or suburban areas where land availability is not a restrictive factor and a lower upfront cost is preferred.
Air Insulated Switchgear FAQs
What is the main insulating medium utilized in AIS? The main insulating medium is the ambient air surrounding the live conductors at atmospheric pressure, which dictates the large physical distances required between components.
What is the biggest operational drawback of an AIS substation? The biggest drawback is the very large land area required for installation, as well as its vulnerability to environmental contamination like dust, salt, and pollution, which can reduce its reliability.
In which environments is AIS generally the most economically practical choice? AIS is most practical in rural or suburban areas where land is abundant and inexpensive, and the equipment is less exposed to severe atmospheric pollution or extreme space constraints.
